Convenience of use is an important aspect in the development of pharmaceutical and nutritional dosage forms. This convenience results in improved user compliance with the desired dosing regimen. A particular aspect of convenience of oral dosage forms is the ability to consume these without access to water or other liquids to aid in swallowing. This benefit is especially important to those who are travelling or who do not have ready access to liquids. Preferred portable dosage forms are chewable products, or products that dissolve readily in the mouth without chewing. Not surprisingly, great effort has been expended in the pharmaceutical and nutritional industries in the development of these convenient dosage forms. The intent of the current invention is to achieve these objectives with an economical, versatile manufacturing process.
U.S. Pat. No. 4,251,561, incorporated herein by reference, describes the preparation of a stable aerated confection which is prepared by forming a confection melt consisting of dextrose and a protein material. The melt, which is heated to about 75 to 110.degree. C., is aerated by the injection of gas under pressure. The foam may be extruded from a die, and the extruded material cut into desired lengths after solidification of the sugar/protein foam. Examples of proteins that may work in this application include gelatin, soy protein, and egg albumin. Candy products may be formed by the addition of appropriate flavors.
U.S. Pat. No. 4,714,620, incorporated herein by reference, discloses the manufacture of various aerated confectionery compositions. The process consisted of making a frappe (including gum arabic, gelatin, hydrogenated starch hydrolysate, and hydroxypropylmethylcellulose (HPMC)). A syrup (including hydrogenated starch hydrolysate, mannitol, and optionally a thickening agent) is prepared by cooking at 180.degree. C. The syrup is then cooled to about 130.degree. C. and added to the frappe by mixing at low speed. Other materials, such as fat, flavor, or color could optionally be added during the mixing operation. The aerated product could be cut or formed into final shapes, and then wrapped. The patent does not disclose the addition of medicaments, particularly coated particles of medicaments, to these compositions, presumably because the high temperatures involved in the manufacture of these compositions would damage the integrity of the coating of any coated drug particles added during manufacture, thereby vitiating the taste masking benefits obtained with these coated particles.
According to U.S. Pat. No. 5,393,528, a foam for the vaginal delivery of active materials can be prepared by mixing HPMC, glycerin, and the active ingredient, and introducing nitrogen gas while mixing to form a frothy foam. The mixture is then cast as a foamed film on a solid surface. Alternatively, the frothy foam can be dispensed into a mold to yield a formed device such as a diaphragm. Polyethylene oxide or polyvinyl alcohol may be used in place of HPMC as a foaming agent. The patent does not discuss the oral consumption of these foams, or the incorporation of coated particles of active ingredient in these foams.
A foamed ibuprofen-containing dosage is disclosed in German patent application 19635676. A mixed copolymer of N-vinylpyrrolidone and vinyl acetate is melted with ibuprofen. The melt is impregnated with carbon dioxide gas while being passed through an extruder. The carbon dioxide expands to yield bubbles impregnated in the melt after it exits from the extruder. The ibuprofen in this foam was co-dissolved with polymer, and therefore the foam would probably impart the unpleasant taste of ibuprofen to the oral cavity when the foam was chewed or allowed to dissolve in the mouth. Additionally, the entrapped bubbles of carbon dioxide could impart an additional bitter taste to foam.
Despite the disclosures of the prior art there is an ongoing need to prepare good tasting, quick dissolving matrices for the delivery of pharmaceutically active ingredients.